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State-owned enterprise Landcorp owns two farms in the Waipori area, both of which have land bordering Lake Mahinerangi.
However, it faces the problem of fencing hundreds of kilometres to stop stock entering waterways.
As a potential solution, this week it started a two-month trial, run by AgResearch, to test virtual fencing technology.
This means cattle can be contained to an area from behind a computer.
The trial involves taking 100 Angus steers at one of the farms, Waipori Station, and equipping half with solar-powered collars that show their location through GPS.
Farmers can draw sensitive areas on a virtual map where they do not want the steers to go.
If this does not work, the animal receives a single electric "pulse" to the back of its neck.
The technology has other features, such as turning off functions when it notices the animal is stressed.
When it calms down the collars use audio cues to herd it back to the right location.
The trial is using "eShepherd" by Australian company Agersens.
While eventually the idea was for the technology to be used in place of other boundaries, the trial was in a well-fenced area.
Pamu Farms innovation specialist Roo Hall said small trials in Australia showed the animals became "in tune" with the audio cues.
It was the first virtual fencing trial in a commercial beef herd in New Zealand, he said.
The company hoped to introduce the technology as a cheaper alternative to physical boundaries in large areas.
"Looking at Lake Mahinerangi, there would be over 500km of fencing we would need to do, which is quite substantial.
"We want to be leading innovators in pastoral agriculture."
New regulations were being introduced making requirements for fencing around waterways stricter, he said.
"Even if wasn’t mandatory, there would still be that drive from us."
At Lake Mahinerangi, there were lake areas which were "pretty sensitive to livestock".
"We have been excluding stock from those areas as much as possible."